Lidar sensors are getting more sophisticated, often consisting of multiple pairs of laser emitters and receptors, each pair being referred to as a beam. Multi-beam Lidar sensors have significant utility for a variety of automotive applications that include safety applications and autonomous driving. Lidar sensors conventionally provide both a 3D spatial component and a reflectivity measurement of the material being struck by each laser beam. The reflectivity measurement may be a very useful source of information about the environment. However, empirical testing on commercially available Lidar units has shown that calibration of the reflectivity measurement is often poor.